Oslo — Norwegian prosecutors officially indicted Anders Behring Breivik, the self-confessed gunman behind last year's July 22 twin terror attacks, on charges of committing a terrorist attack and premeditated murder. But because Mr. Breivik was declared to be in a psychotic state at the time of the attack, prosecutors are seeking a sentence of compulsory mental care, rather than imprisonment.

The terms of today's indictment were expected, given Norway's Forensic Board’s conclusion last year that Breivik is psychotic and therefore not punishable under Norwegian law for the 77 killed in Norway’s worst national tragedy during peacetime.

However, the indictment provides grounds to pursue a prison sentence for Breivik if the prosecution changes its mind during the trial. Breivik was charged with committing a terrorist act and premeditated murder, first during the government bomb blast in Oslo that killed eight and later that day in the mass shooting spree on the island of Utøya at the Labor party’s summer youth camp that led to 69 deaths.

Svein Holden, Oslo public prosecutor, told The Christian Science Monitor that the prosecution would disclose its decision on whether to alter the indictment during closing arguments of the 10-week trial, which is set to start on April 16. One of the key factors in its decision will be the conclusion from the second court-ordered psychiatric evaluation, which is due on April 10.

“If they come to the same result as the last two [psychiatrists], then we probably won’t [change the indictment],” Mr. Holden says.

If the new set of psychiatrists declares Breivik to be sane – and the judges concur – he could face 21 years in prison for terrorism. That would mark a historic legal precedent in Norway. There has been only one previous charge of terrorism and no convictions, according to Holden.

Breivik has admitted to the actions that day, but has pleaded not guilty, citing self-defense as the basis for his plea in his custody hearing last month. He said both attacks were a “preventive attack on traitors” because the Labor-led government was promoting “Islamic colonization” of Norway.

Today’s indictment reveals also that the prosecution will not base its case on crimes against humanity, which carries a sentence of 30 years in Norway. Holden confirmed that it had considered that possibility but felt that terrorism charges best encapsulated all the crimes for which Breivik is accused.

The case is also significant in the magnitude of the charges. The indictment reveals that in addition to the eight killed during the bomb blast, nine were seriously injured and 200 hurt. He also shot and injured 33 people at Utøya in addition to the 69 killed and created panic among the 564 people – mostly teenagers – trapped on the island.

“The defendant has committed extremely serious offenses on a scale that has never previously been experience in our country in modern times,” the prosecutors said.